def safe_divide(a, b):
    if b == 0:
        return None
    else:
        return a/b
    
def convert_to_number(text):
    try:
        answer = int(text)
        return answer
    except ValueError:
        return None
    
# if __name__ =="__main__":
    # print(safe_divide(5,0))
    # print(convert_to_number("39z"))